JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.1/themes/base/jquery-ui.css">
<div id="blocks">
    <div id="block1">Resize me</div>
</div>

CSS

#blocks > div {
    position: absolute;
    background: #fcc;
}
#block1 {
    left: 200px;
    width: 200px;
    height: 100px;
}

JavaScript

$('#block1').resizable();

$(document).mousedown(function(e){
    var block = $('<div id="new">New</div>')
        
    $('#blocks').append(block)
    block.css('left', e.pageX).css('top', e.pageY).resizable()
})